MOBILE, Alabama
A fresh crop of tarballs could be seen rolling in the surf along the barrier islands of Alabama and Mississippi on Thursday, pushed ashore by the surging tide and high waves associated with Tropical Storm Lee last week.
A Thursday inspection of the uninhabited beaches of Dauphin and Petit Bois islands suggests that in addition to bringing new tarballs ashore, the storm either carried away or covered up tar deposits that had been left in place for months amongst sand dunes above the normal high tide line.
The new tarballs ranged from the size of a quarter to blobs 8 inches across, and had a different consistency than those that had been sitting exposed on the uninhabited beaches since last summer.
Moist and gooey, like a chocolate chip cookie just pulled from the oven, some of the fresh tarballs had layers of liquid oil inside them. Oil bled from the tarballs sitting in the sun on the beach, collecting in little pools on the sand.
Ed Overton, an oil chemist and professor emeritus at Louisiana State University, said the tarballs that had been sitting out on beaches for months had weathered almost to the point of being asphalt, dry and crumbly to the touch.
He said the new tarballs likely broke off from mats buried underwater and seemed to share the characteristics of fresh tarballs, which he described as “jellybeans” — crusty on the outside with jelly in the center.
State and federal officials, as well as BP crews, have reported finding numerous tar mats offshore of Gulf beaches. In some cases, the mats are more than a foot thick.
“A lot of people are saying the tar mats are heavily weathered. Well, I bet these tar mats have not been heavily weathered,” Overton said. “These new deposits are probably fresher oil. They’ve been in a protected layer without a lot of agitation. These are probably more like globs of oil.”
Overton said the emergence of buried tar mats during storms is part of a natural progression after such spills.
“It sounds like there was a fairly thick lens of oil out there that had not mixed with sediment. We’re going to be seeing this for years,” Overton said. “This is an irritation compared to what we had last year. Last year was a disaster, this is, ‘Oh no! We’ve got to clean up the beaches again.’ But don’t be surprised when this happens again.”
BP officials said the company sent shoreline assessment teams out along the Gulf Coast after the storm passed and deployed crews to begin collecting tarballs. Justin Saia, a BP spokesman based in Alabama, said a crew collected 35 pounds of tarballs on the inhabited portion of Dauphin Island on Thursday.
“I guess it’s not really surprising that fresh material like that would show up in the shallow waters along the beachfront. The storm was fragmenting these much-reported tar mats offshore,” said John Valentine, senior marine scientist at the Dauphin Island Sea Lab. “But I haven’t seen any maps yet that show where these tar mats are. At this point, it’s just gossip. They need to release the data that show where these tar mats are.”
Valentine said that research from the 1979 Ixtoc spill off Mexico showed that oil can persist for years, buried under the sand in shallow water.
While there were no large mats of tar visible in the water along the islands Thursday, large numbers of tarballs could be seen rolling in the surf in some locations, particularly near collection zones along the shore. Digging into the sand in about 8 inches of water yielded a tarball in every scoop in some areas.
“In a way, that small storm could have been kind of a blessing. We got to see a little of what is out there,” said Gunter Guy Jr., commissioner of the Alabama Department of Conservation and Natural Resources.
Guy said the presence of new tarballs also means the response to the oil spill is not over.
“From that perspective, we have to be careful about which restoration projects we get involved in,” Guy said. “We need to move carefully. That’s something we’ve discussed with BP. It may be a while before the response to the spill is complete.”
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